Changeset 97b1dfc2 in mainline for uspace/lib/posix/src/unistd.c

Timestamp:

2018-09-24T15:36:21Z (7 years ago)

Author:

Jiří Zárevúcky <jiri.zarevucky@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

34c76e2f

Parents:

631281d

git-author:

Jiří Zárevúcky <jiri.zarevucky@…> (2018-09-24 15:02:32)

git-committer:

Jiří Zárevúcky <jiri.zarevucky@…> (2018-09-24 15:36:21)

Message:

Make libposix headers understand _FILE_OFFSET_BITS and _LARGEFILE64_SOURCE

File:

• uspace/lib/posix/src/unistd.c (modified) (3 diffs)

uspace/lib/posix/src/unistd.c

@@ -34 +34 @@
  */
 
+#define _LARGEFILE64_SOURCE
+#undef _FILE_OFFSET_BITS
+
 #include "internal/common.h"
 #include <unistd.h>
@@ -234 +237 @@
 }
 
+static off64_t _lseek(int fildes, off64_t offset, off64_t max_pos, int whence)
+{
+        vfs_stat_t st;
+        off64_t new_pos;
+
+        switch (whence) {
+        case SEEK_SET:
+                new_pos = offset;
+                break;
+        case SEEK_CUR:
+                if (__builtin_add_overflow(posix_pos[fildes], offset, &new_pos)) {
+                        errno = EOVERFLOW;
+                        return -1;
+                }
+                break;
+        case SEEK_END:
+                if (failed(vfs_stat(fildes, &st)))
+                        return -1;
+
+                if (__builtin_add_overflow(st.size, offset, &new_pos)) {
+                        errno = EOVERFLOW;
+                        return -1;
+                }
+                break;
+        default:
+                errno = EINVAL;
+                return -1;
+        }
+
+        if (new_pos < 0) {
+                errno = EINVAL;
+                return -1;
+        }
+
+        if (new_pos > max_pos) {
+                /* The resulting file offset is too large for the interface. */
+                errno = EOVERFLOW;
+                return -1;
+        }
+
+        posix_pos[fildes] = new_pos;
+        return new_pos;
+}
+
+static off64_t _lseek64(int fildes, off64_t offset, int whence)
+{
+        return _lseek(fildes, offset, INT64_MAX, whence);
+}
+
+off64_t lseek64(int fildes, off64_t offset, int whence)
+{
+        return _lseek64(fildes, offset, whence);
+}
+
 /**
  * Reposition read/write file offset
@@ -245 +302 @@
 off_t lseek(int fildes, off_t offset, int whence)
 {
-        vfs_stat_t st;
-
-        switch (whence) {
-        case SEEK_SET:
-                posix_pos[fildes] = offset;
-                break;
-        case SEEK_CUR:
-                posix_pos[fildes] += offset;
-                break;
-        case SEEK_END:
-                if (failed(vfs_stat(fildes, &st)))
-                        return -1;
-                posix_pos[fildes] = st.size + offset;
-                break;
-        }
-        if (posix_pos[fildes] > INT64_MAX) {
-                /* The native width is too large for the POSIX interface. */
-                errno = ERANGE;
-                return -1;
-        }
-        return posix_pos[fildes];
+#if LONG_MAX == INT64_MAX
+        return _lseek64(fildes, offset, whence);
+#else
+        return _lseek(fildes, offset, LONG_MAX, whence);
+#endif
 }